The present invention generally relates to devices for dispensing fluids, in particular beverages. More particularly, the invention concerns devices that have self cleaning dispensing nozzles intended in particular to be used in xe2x80x9cpost-mixxe2x80x9d type dispensing machines for dispensing microbiologically sensitive products, such as milk-based beverages, which are capable of obstructing the dispensing nozzle or allowing micro-organisms to grow therein. In addition, the present device can also be used for dispensing other types of beverages.
The invention also relates to a method for cleaning and a method for setting a dispensing nozzle to a predetermined temperature.
Post-mix type beverages are widely used in beverage dispensers located in fast food restaurants. In such dispensers, a concentrated beverage or syrup is mixed with several measures of water and is then fed to a nozzle to make a finished beverage ready for consumption by the consumer. It will be understood that, for obvious reasons of hygiene, the dispensing nozzles have to be cleaned regularly in order to prevent a build up of bacteria that can particularly develop in the supply lines that bring the concentrate to the dispensing nozzle. These problems are all the more important when the beverages dispensed include milk-based products insofar as these products are very sensitive to bacterial pollution and quickly decompose or deteriorate to poor tasting or inedible products.
Moreover, after a certain number of uses, solid residues of concentrate build up in the nozzle. In addition to altering the taste and/or quality of dispensed beverages, these build-ups also can disrupt the supply of the liquid or even clog the nozzle to reduce or terminate its dispensing ability.
In order to overcome these problems, maintenance personnel regularly dismantle, check and cleanse such beverage dispensing nozzles. These maintenance operations have the drawbacks of being expensive, requiring that the dispenser be taken out of service to be momentarily inoperative, and necessitating contact of the parts that can result in recontamination.
Certain manufacturers have attempted to overcome these drawbacks by proposing dispensers that have structures that allow the nozzles to be rinsed and/or cleaned in order to avoid manual dispenser maintenance. Examples can be found for example in U.S. Pat. Nos. 4,979,527 and 5,749,494. However, the structures proposed to date have proved to be complex and expensive but without providing the desired improvements in cleaning efficiency.
Another problem that these beverage dispensers generally have is linked to the dispensing of hot or cold beverages at the desired temperature, which for hot beverages is typically between 65 and 75xc2x0 C. Indeed, after flowing through supply pipes, mixing with beverage concentrate at 25xc2x0 C., and finally passing through the nozzles, water that is initially heated to approximately 90xc2x0 C. generally has a temperature of less than 55xc2x0 C. when being dispensed from the nozzle. In a fast food restaurant, this temperature is often insufficient for dispensing a so-called xe2x80x9chotxe2x80x9d beverage, particularly if one also takes account of the average time necessary for the consumer to find a table and sit down, during which time the beverage continues to cool. A similar problem arises when one wishes to dispense a cold beverage, as the beverage begins to warm to room temperature. This problem is made worse when a single dispensing device is used to alternatively dispense hot and cold beverages, as the temperature of one counteracts that of the other. Accordingly, there is a need for improved dispensing devices that are not subject to these problems and disadvantages.
The present invention now resolves the problems of the prior art by providing a fluid dispensing device for dispensing fluids such as beverages. This device includes a self-cleaning nozzle assembly, which has a simple and economical structure and which allows efficient rinsing and cleaning (hereinafter referred to by the general term xe2x80x9ccleaningxe2x80x9d) of the dispensing nozzle.
A fluid dispensing device of this type provides a number of advantages:
it allows beverages to be dispensed in optimum conditions of hygiene;
it allows beverages to be dispensed with a consistent taste quality; and
it limits heat exchanges between the water and the conduits and nozzle when preparing and dispensing hot or cold beverages.
The invention specifically relates to a fluid dispensing device comprising: a self-cleaning dispensing nozzle having an outlet; a body having an exterior surface and being provided with a conduit having a first end to which the dispensing nozzle is connected and a second end which can receive a fluid inlet line; a collector member which can move relative to the body between a first dispensing position in which the nozzle outlet is released from the collector member and a second cleaning position in which the collector member can collect fluid that exits the nozzle outlet.
As a result of these features, one obtains a dispensing device with a simple structure wherein, particularly, the nozzle does not need to be dismantled by specialized personnel to be rinsed and cleaned. Indeed, the nozzle can easily be brought into the cleaning position by entering a manual or automatic command for automatic rinsing and cleaning after each beverage is dispensed or with any other desired frequency.
According to a preferred embodiment of the invention, the collector member has the general shape of a sleeve in which the body and the dispensing nozzle are guided for sliding movement along an axial direction. The inner wall of the sleeve along with the outer wall of the body define, in the cleaning position, a cleaning chamber into which extends the dispensing nozzle outlet.
With these features, a cleaning liquid or rinsing fluid (hereinafter referred to by the general term xe2x80x9ccleaning fluidxe2x80x9d) can flow not only into the nozzle but also at the periphery of its outlet so that complete rinsing and cleaning thereof is obtained. In particular, the nozzle can be cleaned thoroughly by the flow of a cleaning fluid such as a detergent or caustic solution. The arrangement of the invention also allows a satisfactory level of hygiene to be maintained for the nozzle during operation via the flow of hot water or water at ambient temperature through the conduit to physically flush out the micro-organisms and prevent them reaching unhygienic levels. The arrangement of the invention also allows to remove scale deposit in the device via the flow of an acid solution or any other suitable descaling agent.
According to another aspect, the invention also relates to a method for cleaning a dispensing nozzle of a fluid dispensing device comprising: the dispensing nozzle; a body having an exterior surface and being provided with a conduit having a first end to which the dispensing nozzle is connected and a second end which can receive a fluid inlet line; a collector member which can move relative to the body between a first dispensing position in which the nozzle outlet is released from the collector member and a second cleaning position, with the nozzle being initially in the dispensing position. This method comprises the steps of: placing the nozzle facing the collector member; flowing a cleaning or rinsing fluid through the conduit and nozzle; collecting the cleaning or rinsing fluid that exits the nozzle in the collector member; and replacing the nozzle back into the initial position.
According to yet another aspect, the invention concerns a method for setting the temperature of a dispensing nozzle of a fluid dispensing machine comprising: the dispensing nozzle; a body having an exterior surface and being provided with a conduit having a first end to which the dispensing nozzle is connected and a second end which can receive a fluid inlet line; a collector member which can move relative to the body between a first dispensing position in which the nozzle outlet is released from the collector member and a second temperature setting position in which the collector member is placed in front of the nozzle outlet, with the nozzle being initially in the dispensing position. This method comprises the steps of: placing the nozzle facing the collector member; causing a temperature setting fluid to flow at a determined temperature through the conduit and nozzle; collecting the fluid coming out of the nozzle in the collector member; and then replacing said nozzle in the initial position.
As a result of these features, the temperature of the dispensing nozzle can be set, i.e. it can be preheated or cooled, simply via the flow of a small quantity of fluid respectively at a high or low temperature in order to bring the temperature of the surfaces of the nozzle in contact with the beverage to be dispensed to the closest possible temperature to the desired temperature. The hot beverage required by the consumer can then be dispensed at a satisfactory temperature. Since this temperature setting operation is quick, it can easily form part of the beverage dispensing cycle and the nozzle can thus be preheated or cooled before each beverage is dispensed.